Dental equipment



May 19,1931. M. D. GOLDBERG DENTAL EQUIPMENT Filednu 28, 1929 4 50 INVENTOR z B p AT TORNEY Patented May 19, 1931' MEYER D. GOLD-BERG, OF PHILADELPHIA, {PENNSYLVANIA DENTAL EQUIPMENT Application filed August 28, 1929. Serial No. 388,878.

This invention relates to dental equipment. It is particularly directed to a device for breaking up and sifting dentists plaster or the like powdered material.

An object of this invention is to provide a device of the character described wherein the original can or container of powdered plaster, may be directly mounted on the device and retained thereon until empty, whereby the plaster may remain stored in the can until used and all of the plaster quickly and efiiciently broken up and sifted without repeatedly opening said can to the room each time plaster is to be removed therefrom, thus preventing absorption of moisture by the plaster.

A further object of this invention is to provide in a device of the character described, improved means for positively con- EU trolling the passage of plaster from the can to the sifting mechanism.

Another object of this invention is to provide a device of the character described having improved means for sifting and breaking up the lumps of plaster to free-the latter of any air bubbles.

A still further object of this invention is to provide means for preparing the plaster in the can for etficient and rapid mixture 39 with water directly upon removal from the container, to substantially prevent unequal setting of the plaster.

Still another object of this invention is to provide a neat, compact and rugged de-' vice of the character described which shall be comparatively.inexpensive to manufacture, comprise few and simple parts, easy to .assemble, disassemble, and manipulate, clean in use, and yet practical and efficient to a high degree.

- Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the features of construction, combinations of elements, and arrangement of parts which will be exemplified in the construction hereinafter described, and of which the scope of application will be indicated in the following claims.

In the accompanying drawings, in which is shown one of the various possible illustrative embodimentsof this invention,

Fig. lis a cross-sectional'elevational View of a device embodying the invention; v

Fig. 2 is a cross-sectional view taken on line 22 of Fig. 1

Fig. 3 is a top plan view of mechanism; and

Fig. 4 is a cross-sectional view. taken on the valve line 14: of Fig. 1'.

Referring now in detail to the drawings, 10 designates a device embodying the invention for sifting and preparing plaster or the like powdered material foruse by dentists and for similar purposes. The plaster is usually purchased by dentists in a can 11 or similar container having an annular neck 12. In accordance with this invention, the cover for saidcan is replaced by valve mechanism 14, hereinafter to be described in greater detail, the can and at tached mechanism thereafter being invertible for mounting the same on .the sifting device in position for use; The device v10 may comprise a hopper l5 of substantially rectangular horizontal cross-section having a pair. of oppositely disposed inclined walls or shoulders 16, a-reduced portion 17 extending downwardly therefrom and terminatingin a funnel shaped portion 18. Said hopper may be supported on suitable legs 19 .formaintaining the lower open end 20 of the funnel in spaced relation above the base or table 21. The usual rubber bowl 21a adapted to contain water for mixing with the plaster may be placed on the base 21 beneath the funnel opening.

For controlling the flow of plaster from the funnel portion 18 to any suitable recepoFFicEfl tacle placed therebelow on said base, a valve 22 is provided for covering the mouth of said funnel. Said valve 22 preferably comprises a pair of horizontally disposed symmetrical gates or doors 23 hinged on a vertical pin 24 rigidly secured in any suitable manner to the funnel 18. Said gates 23 are adapted to be swung or moved into closing position with the inner edge portions 25 of said gates overlapping by means of a handle member 30. Said gates may furthermore be formed with notches 26 for receiving a vertical pin 27 at the lower end of said funnel 18, and grooved as at 28 to form a head 29 for supporting the outer ends of said gates when in closed position.

Mounted within the hopper 15 and sup-v ported by the inclined walls 16 is a sieve having a substantially semi-cylindiiical tion 36 and inclined walls 37 extending tangentially outwardly from said portion 36 and contacting the inner surface of each of said inclined walls or shoulders 18. A reinforcing sheet 100 may be attached to the underside of the sieve 35 in any suitable manner, said sheet having a central opening 101 to permit the plaster to pass therethru. For agitating the powder within the hopper 'to loosen and break up the lumps into a fine powder and to force the same through the sieve'35, an agitator member 38 is provided having a plurality of vanes 41 comprising radial spokes 42 interconnected by horizontal rods 43 mounted on aligned hubs 44 rotatable on stub shafts 39 fixed to the hopper in any suitable manner. One of said shafts; 39 extends beyond the hopper and is formed with a non-circular hea-dfor receiving and coacting with the wrench portion 46 of a crank handle member 48, whereby the agitator 38 may be rotated. It will be noted that upon rotating said agitator, the horizontal portion 43 of each of" the vanes '41 describes a cylindrical surface closely adjacent the semi-circular wall 36 of the sieve 35. This movement causes the powder,- "such as plaster or the like material, within the hopper to be worked through the sieve 36 and opening 101 in sheet 100. It will be noted that since the portions 37 of the "sieve extend at a :tangent to the round surface 36 thereof, the arms43 of the actuating member will not "be adjacent the "sieve untilsaid arms have been rotated to a distance below the shoulder 16 "of the hopper and are substantially over the opening 101.. -;"Wit l1 this construction, clogging or blocking of the material in the hopperadjacent the shoulder portions 36 'is substantially eliminated.

Mounted on the top open end portion 550 of said hopper is a platform 51 having a plurality of depending flanges 52 frictional- 1y contacting the inner surface '53 of said end portion for --removabl-y positioning said platform on said hopper. Extending upwardly from said platform 51 are a plurality of suitably spaced flanges 55 for re movably positioningthe valve mechanism 14 on said platform. Said valve mechanism 14 may comprise a cylindrical wall 56 formed with a pair of diametrically disposed horizontal transverse slots 57. Slidably extending throughone of said slots is a shutter or valve plate 58 having opposite side edge portions 59 received in the grooves formed by a pair of spaced, horizontal, parallel guide members 60, secured within said cylindrical Wall 56 forslidably supporting said valve plate. Said valve member 58 may be provided with a handle'GOa at the inner end thereof. A second valve member 58a substantially similar in construction to said mei-nber -58 slidably extends through the tions '61, 61a of said members. Said valve members .58, 580, may furthermore be provided with depending portions 63 adapted toicontactisaid wall '56 for limiting the inward movement of said valve members; As shown in Figs. -1 and 2 of the drawings, the

lower edgeportion 56a, of said wall56 is adapted to engage the :outer surfaces of the upwardly extending flanges '55 for positioning the valve members on said platform.

It will be noted, furthermore, that the neck 12 of the can 11 is frictionallyrewived in the upper edge portion 56b ofsaid wall '56 for removablyattaching the can tov the "valve mechanism 14. In use, the valve mechanism 14' may beremoved from the platform 51 and attached :to the neck of the can 11 with the valve plates 58,158a closed, as described above. The can with the attached valve mechanism 14 may thereafter be inverted and mounted on the platform :51 and the valve plates 58 and 58a thereafter moved to any suitable adjusted position to permit passage of plaster from the can to the hopper.

Thus, the plaster remains in the can until used and all of thee-plaster may be used. directly from the original can without necessitating repeated removal .of :the can cover and exposure to the air, whereby absorption of moisture bjVithe plaster is substantially eliminated. Obviously, when. the container has been emptied by such use, the sieve may be lifted out and foreign substances that Since the device herein described obviates the use of the usual dentists spatula for conveying plaster from the can to the mix ing bowl, loss and spillage of said plaster on the floor and table is prevented and hence said device may be used in a laboratory, or the operating room or the like place which must be kept clean.

It will further be noted that the lumpy plaster from the can is broken up, freed from air bubbles, and sifted, and then drops down into the mixing bowl from some height, hence providing a rapid supply of finely powdered plaster to the water in the bowl whereby a quick mixture may be made to prevent unequal setting or hardening of the plaster in the bowl.

It will thus be seen that there is provided a device in which the several objects of this invention are achieved, and which is well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiment set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

character described comprising a hopper open at the upper and lower ends thereof, a

valved closure member at the top of an end of said hopper, a sieve in said hopper and a valve at the lower open end of said hopper,

said last named valve comprising a pair of In testimony whereof I afiix my signature.

MEYER D. GOLDBERG.

Having thus described my invention, I

claim as new and Patent:

1. In combination, a sifter and dispensing device comprising a hopper having upper and lower open end portions, means within said hopper for sifting powdered material, an adjustable valved closure member remova-bly mounted on said upper end portion of said hopper, a container having an open end and being otherwise closed, removably mounted on said member with the open end of said container adjacent said member, and an adjustable valved closure at the lower end of said device.

2. A dispensing device comprising a hopper having means for sifting powdered material, and a valved closure member removably mounted on said hopper, said member comprising a cylindrical wall, and a pair of plate members mounted on said wall for sliding movement toward and away from each other for regulating the size of the valve opening for said member.

3. A dispensing device comprising a hopper having means for sifting powdered material, and a valved closure member removably mounted on said hopper, said member comprising a cylindrical wall, and a pair of plate members mounted on said wall for sliding movement toward and away from each other for regulating the size of the valve opening for said member, the inner adjacent edge portions of said plate members overlapping and being inwardly curved.

4. A sifter and dispensing device of the desire to secure by Letters 

